I have a 56 Victoria, serial number would indicate a 312. I cannot get the idle to 400-500 and still have the car run decent. So, when the car runs correctly and I move the gear shift into reverse it slams. One mechanic suggested that I have the tranny looked at. A good shop said the tranny is fine, Just idles too fast. I have the PCV line reduced to 3/16 and venting into the air cleaner. I have Holley 4170---is  it too big. I have read some forum's that hint at that. Help=Please. Harold

What is your idle rpm? Stock camshaft?  How many miles on the engine? What ignition system?  L-O-M or ’57 and later model?  Where is the initial ignition timing set at? Have you tried it with the PCV valve disconnected?  Is the distributor vacuum hooked up to the ported or direct vacuum port on the carburetor?

Lorena, Texas (South of Waco)

Thanks Ted, will follow up on all most of your questions and put on Forum.Harold

One thing to consider if it is a 56 V8 and has a H4150/4160 retrofit (ECZ-A or ECZ-B intake?), and if AT (FOM), is the carb throttle linkage has to be adjusted with the TV linkage disconnected and once proper curb idle is established adjust the TV linkage from there.

Possibly use a VACUUM GAUGE to determine if any vacuum leaks. Is the DIST USED A LOAD-O-MATIC or 1957/ DUAL ADVANCE?

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